My Pi is destined for the skies, so it will receive power at roundabout 5.3V via the BEC (battery eliminator circuit) which will be capable of delivering up to 10A (heavy duty BEC it is), so sourcing the actual power will not be a problem.
Also not a problem is splicing a Micro USB male cable for delivering power the normal way.
However, my Wifi adapter, a TP-LINK TL-WN722N may not be fully powered due to various factors if the Micro USB plug is the only source. The selling point is "High Gain"! I may need it, there might be some distance to cover, after all.
So I wonder what the best approach is? Should I send power to the Pi simultaneously via the 5V pin on the GPIO header and the Micro USB cable? Should I build a modified USB A male plug (or splice the connection in such a way) that will pass the data pins through to the Pi but divert the Wifi module's 5V USB power straight to the same source of 5V power as the USB cable? Should I make all three connections?
My hope is that the 5V GPIO pin should be directly wired up to the USB 5V supply that goes to the WiFi adapter.
So the question then would be whether it is the case that as long as I also have the Micro USB plug also providing the power, (and not with the GPIO being the only source of power) that I should no longer be at risk of frying (or distressing) anything.